microsome
Noun: A small, membrane-bound particle or vesicle found within the cytoplasm of a cell, especially as a fragment of the endoplasmic reticulum produced during laboratory homogenization and centrifugation. Microsomes are not naturally occurring organelles but are artificial structures used in biochemical studies to investigate cellular processes like protein synthesis and drug metabolism.
Microsomes are primarily discussed in scientific contexts, specifically cell biology, biochemistry, and pharmacology. The term is used to describe the prepared cellular fragments used for in vitro (in glass) experiments. - Scientists isolate liver microsomes to study how the body metabolizes new drugs. - Protein synthesis can be studied using a cell-free system containing ribosomes and microsomes.
- "Microsomal fraction": The pellet of material collected after ultracentrifugation of cell homogenate, which is enriched in microsomes.
- The microsomal fraction was resuspended in buffer for the enzyme activity assay.
- "Microsomal preparation": A laboratory sample containing microsomes, ready for experimental use.
- The activity of the cytochrome P450 enzymes was measured in the liver microsomal preparation.
- Microsomal (adjective): Relating to or derived from microsomes.
- The microsomal enzymes are crucial for detoxification.
- Cytoplasmic vesicle (a more general term for small membrane sacs in the cytoplasm).
- Endoplasmic reticulum fragments (describes their primary origin more specifically).
It is critical to understand that "microsome" refers to an artificial laboratory product, not a discrete organelle within a living cell. In a living cell, the functions studied using microsomes occur within the intact endoplasmic reticulum and Golgi apparatus. The term is a functional and operational one for biochemistry.
- a tiny granule in the cytoplasm that is where protein synthesis takes place under the direction of mRNA